[unreadable] [unreadable] Dr. Segal is seeking this Mentored Patient-Oriented Award to study the epiderniology of immune thrombocytopenic purpura (ITP) in the United States, to conduct a cross-sectional study examining mercury's association with relevant autoantibodies in patients with ITP, and to initiate the establishment of a cohort of patients with ITP for longitudinal study. These activities will contribute to her becoming an independent clinical researcher. [unreadable] [unreadable] There is scant information on the epidemiology of ITP in the United States. Autoimmune diseases, collectively, are an under-recognized burden on the health care system and ITP may be a substantial contributor, as affected patients require periodic inpatient care, surgical interventions, and often life-long medical therapy. Dr. Segal will use two large national databases, the Nationwide Inpatient Sample and the Nationwide Hospital Ambulatory Medical Care Survey, to investigate the prevalence of disease, sex and gender distribution, comorbid illnesses, and consumption of resources by patients with ITP. [unreadable] [unreadable] The etiology of chronic ITP, as occurs in adults, remains uncertain, but may involve an environmental trigger in patients with a susceptible genotype. To this end, Dr. Segal will collect cross-sectional data aimed at investigating the role of mercury in patients with chronic ITP. She will measure blood and toenail mercury concentrations and autoantibodies which have been associated with low-level mercury exposure, as well as anti-platelet glycoprotein antibodies. It is expected that patients with mercury-associated autoantibodies will have a high prevalence of platelet-specific antibodies. Future research will be aimed at investigating the immunogenotypes of these patients who demonstrate susceptibility to the autoimmune effects of mercury, which may suggest new therapies for this subset of affected patients. [unreadable] [unreadable] Finally, Dr. Segal will pilot the establishment of a cohort of patients with ITP for longitudinal study. This will facilitate collaboration with researchers at other institutions who may be interested in enrolling patients with ITP in cohort studies. [unreadable] [unreadable] Dr. Segal has strong clinical and research training and an early track record in clinical research in blood-related topics including anticoagulation and the epidemiology of autologous blood use. The mentoring by a skilled epidemiologist, an environmental scientist with extensive heavy metal experience, and a hematologist/pathologist with expertise in platelet disorders, will provide Dr. Segal with the necessary support for successful completion [unreadable] [unreadable] [unreadable]